import re
import datetime

# Options default values
STYLE_START_COMMENT = "/*!"
START_COMMAND = "\\"
AUTHOR_NAME = "John Doe"
AUTHOR_EMAIL = "johndoe@email.com"
DATE_FORMAT = "%d/%m/%Y"

def getOptions():
    """ Get options from options.txt file

    Returns
    -------
    None 
    """
    global STYLE_START_COMMENT, START_COMMAND, AUTHOR_NAME, AUTHOR_EMAIL, DATE_FORMAT
    try:
        with open('options.ini', 'r') as file:
            file_content = file.read()
            start_command_match = re.search(r'(?<=start_command = ).+', file_content)
            style_start_comment_match = re.search(r'(?<=style_start_comment = ).+', file_content)
            author_name_match = re.search(r'(?<=author_name = )\w+\s?\w+', file_content)
            author_email_match = re.search(r'(?<=author_email = )\w+@\w+\.\w+', file_content)
            date_format_match = re.search(r'(?<=date_format = )\S+', file_content)
    except FileNotFoundError:
        start_command_match = None
        style_start_comment_match = None
        author_name_match = None
        author_email_match = None
        date_format_match = None

    if start_command_match:
        START_COMMAND = start_command_match.group()
    if style_start_comment_match:
        STYLE_START_COMMENT = style_start_comment_match.group()
    if author_name_match:
        AUTHOR_NAME = author_name_match.group()
    if author_email_match:
        AUTHOR_EMAIL = author_email_match.group()
    if date_format_match:
        DATE_FORMAT = date_format_match.group()

def getFunctions(filename: str) -> list:
    """ Get the prototype of all functions in a file

    Parameters
    ----------
    filename : str
        Name of the file to get the functions from

    Returns
    -------
    list
        List of functions prototypes
    """
    with open(filename, 'r') as file:
        content = file.read()
        pattern_function = re.compile(r'(?<=\n)(?!/\*\*|/\*!)\n+(\w+\s+\w+\s*\([^)]*\))')
        functions = re.findall(pattern_function, content)
    return functions

def getArguments(function: str) -> list:
    """ Get the arguments from a function prototype

    Parameters
    ----------
    function : str
        Prototype of the function

    Returns
    -------
    list
        List of arguments
    """
    pattern_args = re.compile(r'\b\w+\b(?=\s*[,)])')
    return re.findall(pattern_args, function)

def getReturnType(function: str) -> str:
    """ Get the return type of a function

    Parameters
    ----------
    function : str
        Prototype of the function

    Returns
    -------
    str
        Return type of the function
    """
    pattern_return = re.compile(r'\b\w+\b(?=\s+\w+\s*\([^)]*\))')
    return re.search(pattern_return, function).group()

def writeFunctionCommentLines(content: list, index: int, function: str) -> list:
    """ Write the comment block for a function

    Parameters
    ----------
    content : list
        Content of the file
    index : int
        Line index where the function is located
    function : str
        Prototype of the function to comment

    Returns
    -------
    list
        Content of the file with the comment block added
    """
    if content[index].strip().startswith('*/'):
        return content

    comment_lines = [
        f'{STYLE_START_COMMENT} \n',
        f' * {START_COMMAND}fn {function} \n',
        f' * {START_COMMAND}author {AUTHOR_NAME} <{AUTHOR_EMAIL}> \n',
        f' * {START_COMMAND}version 1.0 \n',
        f' * {START_COMMAND}date {datetime.datetime.now().strftime(DATE_FORMAT)} \n',
        f' * {START_COMMAND}brief \n'
    ]

    args = getArguments(function)
    comment_lines.extend([f' * {START_COMMAND}param {arg} \n' for arg in args])

    if getReturnType(function) != 'void':
        comment_lines.append(f' * {START_COMMAND}return \n')
    comment_lines.append(f' */\n')

    content[index:index] = comment_lines
    return content

def writeFunctionComment(filename: str, function: str):
    """ Insert the comment block for a function in a file
    
    Parameters
    ----------
    filename : str
        Name of the file to insert the comment block
    function : str
        Prototype of the function to comment

    Returns
    -------
    None
    """
    with open(filename, 'r') as file:
        content = file.readlines()

    for i, line in enumerate(content):
        if line.strip().startswith(function):
            content = writeFunctionCommentLines(content, i, function)
            break

    with open(filename, 'w') as file:
        file.writelines(content)

def writeFileComment(filename: str) -> None:
    """ Write the comment block for the file

    Parameters
    ----------
    filename : str
        Name of the file to insert the comment block

    Returns
    -------
    None
    """
    with open(filename, 'r+') as file:
        file_content = file.read()
        if re.search(r'(?:\/\*\*|\/\*!)\s*\*\s*(?:\\|@)file\s+(\w+)[\s\S]*?\*\/', file_content):
            return None
        
        file.seek(0)
        content = file.readlines()

        comment_block = [
            f'{STYLE_START_COMMENT} \n',
            f' * {START_COMMAND}file {filename} \n',
            f' * {START_COMMAND}author {AUTHOR_NAME} <{AUTHOR_EMAIL}> \n',
            f' * {START_COMMAND}version 1.0 \n',
            f' * {START_COMMAND}date {datetime.datetime.now().strftime(DATE_FORMAT)} \n',
            f' * {START_COMMAND}brief \n',
            f' */\n\n\n'
        ]

        content = comment_block + content
        file.seek(0)
        file.writelines(content)
        file.truncate()

def generateAllComments(filename: str):
    """ Write the comment block for all functions in a file and the file itself

    Parameters
    ----------
    filename : str
        Name of the file to insert the comment blocks

    Returns
    -------
    None
    """
    getOptions()
    writeFileComment(filename)
    functions = getFunctions(filename)
    for function in functions:
        writeFunctionComment(filename, function)